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Breeding Bunnies Lab
Breeding Bunnies Lab
• Intro: In this activity, you will examine natural
selection in a small population of wild rabbits.
Evolution, on a genetic level, is a change in the
frequency of alleles in a population over a period
of time. Breeders of rabbits have long been
familiar with a variety of genetic traits that affect
the survivability of rabbits in the wild, as well as
in breeding populations.
• One such trait is the trait for
furless rabbits (naked bunnies).
This trait was first discovered in
England by W.E. Castle in 1933.
The furless rabbit is rarely found
in the wild because the cold
English winters are a definite
selective force against it.
• Note: In this lab, the dominant allele for
normal fur is represented by F and the
recessive allele for no fur is represented
by f. Bunnies that inherit two F alleles or
one F and one f allele have fur, while
bunnies that inherit two fs have no fur.
Procedures:
• 1. Use the gene frequency data and
discussion questions and write a hypothesis
and specific predictions based on your
hypothesis.
• 2. You will be working in assigned groups.
Everyone should take turns doing each part
of the lab. Gather all materials Breeding
Bunnies: Gene Frequency Data , Breeding
Bunnies: Discussion Questions, 50 red beans,
50 white beans, 1 paper bag, 2 cups, 1 petri
dish, and pens.
• 3. The red beans represent the allele for fur, and
the white beans represent the allele for no fur.
The bag represents the English countryside,
where the rabbits randomly mate.
Breeding Bunnies: Gene Frequency Data
• How does natural selection affect gene frequency
over several generations?
• 1. Clearly state your hypothesis (a tentative
explanation or solution to the problem).
• ________________________________________
________________________________________
__________
• ________________________________________
________________________________________
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• State what you would predict (if your hypothesis is
true) about the frequency of F alleles and f alleles
in the population of rabbits after 10 generations,
where ff bunnies are selected against (do not
survive).
• ________________________________________
• 4. Label one dish FF for the homozygous dominant
genotype. Label a second dish Ff for the heterozygous
condition. Label the third dish ff for those rabbits with the
homozygous recessive genotype.
• 5. Place the 50 red and 50 white beans (alleles) in the
container and shake up (mate) the rabbits. (Please note that
these frequencies have been chosen arbitrarily for this
activity.)
• 6. Without looking at the beans, select two at a time, and
record the results on the data form next to "Generation 1."
For instance, if you draw one red and one white bean, place
a mark in the chart under "Number of Ff individuals."
Continue drawing pairs of beans and recording the results in
your chart until all beans have been selected and sorted.
Place the "rabbits" into the appropriate dish: FF, Ff, or ff.
(Please note that the total number of individuals will be half
the total number of beans because each rabbit requires two
alleles.)
• 7. The ff bunnies are born furless. The cold weather
kills them before they reach reproductive age, so
they can't pass on their genes. Place the beans
from the ff container aside (petri dish) before
beginning the next round.
• 8. Count the F and f alleles (beans) that were
placed in each of the "furred rabbit" dishes in the
first round and record the number in the chart in the
columns labeled "Number of F Alleles" and
"Number of f Alleles." (This time you are really
counting each bean, but don't count the alleles of
the ff bunnies because they are dead.) Total the
number of F alleles and f alleles for the first
generation and record this number in the column
labeled "Total Number of Alleles."
• 9. Place the alleles of the surviving rabbits (which
have grown, survived and reached reproductive
age) back into the container and mate them again
to get the next generation.
• 10. Repeat steps five through nine to obtain generations
two through ten. If working as a team, make sure everyone
in your group has a chance to either select the beans or
record the results.
• 11. Determine the gene frequency of F and f for each
generation and record them in the chart in the columns
labeled "Gene Frequency F" and "Gene Frequency f." To
find the gene frequency of F, divide the number of F by the
total, and to find the gene frequency of f, divide the number
of f by the total. Express results in decimal form. The sum
of the frequency of F and f should equal one for each
generation.
• 12. Graph your frequencies. Prepare a graph with the
horizontal axis as the generation and the vertical axis as
the frequency in decimals. Plot all frequencies on one
graph. First, plot your own data. Use a solid line (or colored
pencil) for F and a dashed line (or different color) for f.
• 14. Complete the Discussion Questions form with your
group.
• 15. We will discuss all groups’ data when all are done.
Generation
1
2
3
4
5
6
7
8
9
10
Number of
FF
Individ
uals
Number of
Ff
Individuals
Number of
ff
Individuals
Number
of F
Alleles
Number
of f
Alleles
Total
Number
of Alleles
Gene
Frequency
of F
Gene
Frequency
of f
• 2. State your original hypothesis. Based on your lab data,
do you accept or reject the original hypothesis? Explain.
• 3. Compare the number of alleles for the dominant
characteristic with the number of alleles for the recessive
characteristic.
• 4. Compare the frequencies of the dominant allele to the
frequencies of the recessive allele.
• 5. In a real rabbit habitat new animals often come into the
habitat (immigrate), and others leave the area (emigrate).
How might emigration and immigration affect the gene
frequency of F and f in this population of rabbits? How
might you simulate this effect if you were to repeat this
activity?
• 6. How do your results compare with the class data? If
significantly different, why are they different?
• 7. How are the results of this simulation an example of
evolution?
Bunny lab
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1. Testable If… then… hypothesis stated?
2. controlled experiment?
3. Does it test the hypothesis?
4. Data collected
5. Data analyzed/ graphed/explained
6. Is there a clear claim statement?
7. Does the data support the claim?
8. Is there a clear statement of the justification for
the data supporting the claim? ( is your reasoning
explained using scientific terms, laws or theories)
Your assignment:
• To conclude this experience, each of you will
write on your own paper an answer to the
question: How did the Bunny lab
demonstrate natural selection which resulted
in evolution of this population? Do your
results support or reject Hardy-Weinberg
Equilibrium? Explain why or why not. Make
sure to include actual data and/or equations
to support your answers!
• The final lab is due Thursday. Be NEAT and
THOROUGH!
Beans/food gathering adaptations
• This time,you get to design the lab!
• Given the materials, decide on a testable
question about the beans or the organism
hunting the beans. This should demonstrate
natural selection, gene flow or genetic drift.
• If you need more materials ask!
• You must complete the experimental design
plan given to your group and get approval
before you begin.
Self check/ evaluation rubric
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1. Testable If… then… hypothesis stated?
2. controlled experiment?
3. Does it test the hypothesis?
4. Data collected
5. Data analyzed/ graphed/explained
6. Is there a clear claim statement?
7. Does the data support the claim?
8. Is there a clear statement of the justification for
the data supporting the claim? ( is your reasoning
explained using scientific terms, laws or theories)
Your Lab Report Should Have:
• Claim: a statement
• Evidence: data charts, explained to support
your claim… make your case! The data is
what people believe!
• Justification: Why this makes sense! Your
reasoning!